What to do if you misplace or bend anchor bolts:

Damaged or misplaced anchor bolts during the construction process is a very common occurrence, and I will address a few solutions.


Example of bent anchor bolts.

For bent anchor bolts, in certain situations, it is allowable to bend the anchor bolts back into their original position.  See the following statement from the AISC Design Guide 1, 2nd Edition:

“ASTM F1554 permits both cold and hot bending of anchor rods to form hooks; however, bending in the threaded area can be a problem. It is recommended that only Grade 36 rods be bent in the field and the bend limited to 45° or less. Rods up to about 1” in diameter can be cold bent. Rods over 1” can be heated to 1,200° F to make bending easier. It is recommended that bending be done using a rod bending device called a hickey. After bending, the rods should be visually inspected for cracks. If there is concern about the tensile strength of the anchor rod, the rod can be load tested.”

Therefore, it is permitted to field bend F1554 grade 36 anchors that are not bent more than 45 degrees.

If the anchor rods are bent more than 45 degrees or are simply misplaced, then post-installed anchors may be a viable option. New anchors can be drilled and epoxied into the concrete structure, or expansion anchors may be utilized.

All projects are unique with different types of foundation complexities. Therefore, for any of these solutions, the Structural Engineer of Record (SEOR) on the given project must be advised and give their approval.

Allegheny Design Services

Structural engineering is a field of engineering dealing with the analysis and design of structures that support or resist loads. Structural engineers create complex structural systems through the use of simple components.

Allegheny Design Services (ADS) works closely with architects and contractors to provide the engineering support that turn their vision into reality.  To test your structural engineering knowledge, download a case study and to watch a quick video, click here!

Written by Jason Robinson, PE, Senior Structural Engineer

jasonJason works as a Senior Structural Engineer at Allegheny Design Services. His responsibilities include but are not limited to project management, production of construction documents with CAD and structural engineering design. He attended West Virginia University where he received his bachelor’s degree in civil engineering. He has extensive engineering experience as both a field engineer and a structural engineer. He has also acquired skills in the Autodesk Revit 3D modeling system for the production of construction documents.